ΔE 16.2, loose: different enough that you should pick on purpose. Deck Grey is noticeably lighter, cooler than Command Khaki.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Deck Grey is noticeably lighter, cooler than Command Khaki.
The same difference applies the other way round: Command Khaki is noticeably darker, warmer.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Command Khaki on the colour wheel See Deck Grey on the colour wheel
All matches: Command Khaki equivalents · Deck Grey equivalents